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The Bosch Common rail system uses the latest diesel injection technology.
The fuel injection quantity and timing together with control of exhaust emissions are electronically controlled.
Signals from the accelerator pedal position (APP) sensor  together with information from other engine and vehicle sensors are transmitted to the engine control module (ECM) .
An electrical fuel pump  or an engine driven mechanical pump  or both supply fuel at low pressure to the high-pressure pump.
The high-pressure fuel supply is provided by an engine-driven mechanical high-pressure pump . The pump comprises three pumping elements driven by an eccentric shaft.
The pressure is controlled by a fuel pressure control solenoid  mounted on the rear of the pump.
On some applications a 3rd piston cut-off solenoid  is used to enable the pump to operate only two pumping elements, resulting in less engine power being absorbed at low engine loads.
High-pressure fuel from the high-pressure fuel pump is delivered to the fuel rail  where it is distributed to the injectors . Operating conditions in the fuel rail are monitored by the fuel temperature sensor  and fuel pressure sensor .
The fuel injectors are electrically operated by the ECM  and use low-resistance solenoids. To reduce the current being switched by the ECM, the voltage is rapidly switched during the injection period.
The fuel is injected in two stages (or three where exhaust emission standards are higher), firstly the PILOT injection to precondition the combustion chamber, followed very shortly afterwards by the MAIN injection. Some applications where higher exhaust emission standards are required use a third period of injection called POST injection, where fuel is injected into the exhaust stroke and reburnt via the exhaust gas recirculation (EGR) system.